Five-times grand slam champion Maria Sharapova is seeking to have her two-year doping ban wiped out or reduced as she lodged an appeal with the Court of Arbitration for Sport (CAS).
The 29-year-old Russian was banned by the International Tennis Federation (ITF) earlier this month following a positive test for the banned drug meldonium during January's Australian Open.
"In her appeal to the CAS, Ms Sharapova seeks the annulment of the Tribunal's decision to sanction her with a two-year period of ineligibility further to an anti-doping rule violation," sport's highest tribunal said in a statement.
"Ms Sharapova submits that the period of ineligibility should be eliminated, or in the alternative, reduced."
The statement added that her case had been expedited and a ruling would be made by July 18 at the latest, which means Sharapova still harbours hopes of competing at the Rio Olympics in August provided her ban is reduced to time already served.
The former world number one was named in Russia's official entry list for the Olympics tennis tournament.
Sharapova had called the ITF's ruling "unfairly harsh" as an independent tribunal had found that she had not intentionally violated anti-doping rules.
Meldonium was added to WADA's list of banned substances at the start of the year after mounting evidence that it boosted blood flow and enhanced athletic performance.
About 180 athletes have tested positive for the drug, manufactured in Latvia and common throughout eastern Europe, since January.
Sharapova stunned the sporting world in March when she announced that she had tested positive for meldonium, a component of a product named Mildronate which she has taken since 2006 for health issues.